send_contact

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It discloses that the send is immediate, one per call, and displayName is optional (resolved from contactMid when omitted). It could mention permissions or error handling, but the key behavioral traits are covered.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences, front-loaded with the main action, and contains no unnecessary words. Every sentence adds meaningful context.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With 3 parameters (2 required) and no output schema, the description explains what the tool does, how to use it, and key constraints. It does not mention the response or success/failure signals, but for a side-effect tool, the information is sufficient for correct invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3. The description adds value by explaining chatId as a LINE chat/group/room MID, contactMid as coming from find_contact or get_group_members, and displayName's optional behavior. This enriches the schema definitions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description explicitly states the tool shares a LINE contact card to a conversation, specifying the action and resource. It distinguishes from sibling send tools like send_message or send_image by focusing on contact cards and referencing find_contact/get_group_members for the MID.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description clearly indicates the tool is for sharing contact cards and works in 1:1/group/room. It does not explicitly state when not to use it or mention alternatives, but the context from sibling tools makes the intended use case clear.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.